The success came six days later.
True success came when three human beings returned ALIVE from an expedition to the moon on December, 27th
If the rocket motor, or the propellant tanks on the CSM had exploded
during the Apollo 8 Lunar orbital insertion attempt [sound familiar?] then?...
the Soviets could have attempted to try to send a lone cosmonaut onboard a Zond spacecraft to the moon in January, 1969.
And the moon race would have been over; Soviets winning.
No Neil Armstrong on the surface; humanity would have been stuck
in LEO after January, 1969.